EQ6 Worm Gear and Alignment

[darrellx (Darrell)]

Hi All

I have had my EQ6Pro mount for about 8 years, and over the last 6 months or so it has been getting a bit "sloppy" in both axis (axes). So I decided I should open it up and do a bit of a clean and re-grease. It all went fairly well. I downloaded the instructions "Stripping/Rebuilding the Synta EQ6 Mount" by Astro Baby.

I had a really hard time getting both Worm End Float Covers off. I almost got to the point where I was going to drill them off. But, thankfully, I didn't have to. The Worm End Float Adjuster on the DEC axis was nice and firm. However, the Adjuster on the RA axis was so loose it moved around just with the touch of a finger. Probably explains why the RA guiding was causing such an issue.

Anyway, it is all back together and ready to go. And, you guessed it, I do have a question.

Now that it is reassembled, how do I make sure that both axis are "in line"? Lining up by sight seems a bit hit and miss. I tried putting a spirit level on the housing for the RA axis, and it appears okay. But the DEC Axis has nothing I can line up with.

Any suggestions?


By the way, for any wordsmiths out there, is the plural for axis really axes?

Thanks
Darrell

[peter_4059 (Peter)]

What do you mean by lined up?

[darrellx (Darrell)]

Peter

Yeh, I wasn't sure what words to use, or how to easily explain it.

Take the DEC axis. When I got the mount, if I turned the dovetail holder so the arrow lined up with the Zero on the Dec Scale ring, the scope was "lined up" with the axis and truely pointed straight ahead. So when I lined up on the SCP, all was good. Now that I have pulled the mount apart, I need to make sure that the scope is pointing to zero dec when the Scale ring is showing zero. Otherwise, when I am trying to align to the SCP, the DEC axis may be pointing a little to the left or right of the SCP (when viewed from the eyepiece of my refractor).

The same with the RA axis. When I first set up, the counterweight bar should hang straight down, (ignoring the fact that it points forward as a result of being 28 deg south) directly under and centred on the in-build polar alignment scope. When viewed from the front, the bar points straight down to the ground. Other than standing back a distance and adjusting by eye, how do you make sure that the RA axis isn't ever so slightly rotated a bit.

I figure that a slight misalignment in both, or either axis (axes), will make guiding a bit more difficult. Or am I worrying about nothing?


Thanks
darrell

[peter_4059 (Peter)]

Set the cw bar horizontal with a spirit level. Adjust the ra setting circle to 0. Set the dec (fixed side of the dovetail clamp) horizontal with the spirit level and ajust the dec setting circle to zero. Now rotate cw bar to vertical until the ra setting circle reads 90 deg.

[darrellx (Darrell)]

Thanks Peter

That's what I was after. Worked great.

As I read it, I seem to remember you have told me this before - a long time ago.

Darrell

[Astrofriend (Lars)]

Hi Darell,
I use a spirit level when I do it. I have some photos and text here that you can look at:
http://astrofriend.eu/astronomy/proj...nt.html#part04

/Lars